Exercise 18 Page 245

The percent proportion is a proportion that sets the ratio of a part of a whole equal to the ratio of a percent out of 100. We can represent a is p percent of wwith the given proportion. part/whole=percent/100 ⇔ a/w=p/100We can find what number's 0.9% is 36 by thinking about 0.9 as the percent and 36 as a part of the whole. Let's substitute a= 36 and p= 0.9 into the formula and solve for w using the Properties of Equality.

Knowing the value of w, let's look at the completed percent proportion. 36/4000=0.9/100 We found that 3.6 is 0.9 % of 400.